Thermotelephonic receiver



A. WILLAMS ET AL.

THERMUTELEPHONIC RECEIVER.

FILED APR.24,1920.

GHG: uur) Patented Feb. Z, ll..

ALFRED WILLIAMS AND LEO DAFT WILLIAMS, OF LONDON, ENGLAND.

THIERMOTELEPHONIC RECEIVER.

Application filed Avril 24, 1920. Serial No. 376,389.

To aZZ who/n 'it may concern Be it known that we, ALFRED WILLIAMS and Lno DAF'r WILLIAMS, both citizens of the United States of America, residing at London, England, haveinvented new and useful Improvements in Thermotelephonic Receivers, of which the following is a speciiication.

This invention relates to improvements in telephone receivers of the type described in our application Ser. No. 142069 filed Jan. 12, 1917.

^ lVe have Yfound by experiment that thev efficiency of receivers of the type mentioned is considerably improved by arranging the metal foil or leaf in such a manner that the segments or strips of foil or leaf are disposed face to face and1as nearly as practicable parallel to each other and also as near together as is compatible with safety from short-circuiting and with the possibility of obtaining good cooling by convection. By face to face we mean an arrangement in which the strips or segments of foil or leaf face each other as do the two halves of an uncrossed belt connecting two pulleys.

To more fully explain the essential features of the invention, reference is made to the accompanying drawings in which Fig. 1 is an elevation of a simple embodiment of the invention;

Fig. 2 is a plan View thereof; and

Figs. 3-7 inclusive are plan views of modified forms of the invention.

In Figs. 1 and 2 P denotes metal pegs secured in a. base A of vulcanite or other suitable insulating material. On these pegs are supported strips S of metal foil of the character described in our application above referred to. WhileA there is considerable latitude in regard to the length, width and spacino ofthe strips S, we have found that a widt B of 9,-, a length of 5g and a distance C of 33g bring about very good results. "Fg 3 shows astrip T of foil arranged in the form of a spiral having its convolutions disposed in the same general plane and supported on a relatively large number of pegs P1. The distance C1 between the convolutions is preferably the same or approximately the same as the distance C in Figs. 1 and 2.

In Fig. 4 a strip V forms a plurality of triangular convolutions in the same general plane as in Fig. 3. Pegs P2 are correspondingly placed to support the strip. The distance C2 between the convolutions is again substantially the same as C in Figs. 1 and 2.

Fig. 5 shows a zig-zag form of strip lV supported on pegs P3 at the vertices. The length L, is preferably the same as L in Figs. 1 and 2 and the distance C3 between adjacent vertices is also preferably the same as C, Figs. l and 2.

Fig. 6 shows a modified form of zig-Zag arrangement in which the different sections X i'un parallel courses and are supported by correspondingly placed pegs P4 in close proximity to each other, the distance C4 corresponding again to C in Figs. l and 2.

Fig. 7 shows an arrangement differing from the arrangements previously described but having in common with them the characteristic feature that sections'Z of the foil run face to face and are supported by pegs P5 parallel to each other at a distance C5 of the order of C in Figs. 1 and 2.

VVith'in the broader aspect of the inveiition it is possible to provide other forms'or combinations of forms defining the characteristic features above pointed out. l

`While we cannot, of course, precisely and positively explain the reasons why arrangements having the above mentioned characteristics show a greater efficiency .tha ,other forms, it is our opinion that due to t e face to face relation of the strips or sections the amount of heat radiation is reduced although sutiicient provision is made for effective cooling. Whether this explanation is correct must be left to future investigation. The fact remains, however, that all forms of devices above referred to show a marked improvement over other forms not having the characteristics pointed out.

l. In a telephone receiver of the type described, a bridge of metal foil composed of a plurality of sections which are disposed between two adjacent parallel planes, substantially at right angles thereto, some of the sections being disposed face to face in substantially parallel relation to each other.

2. ln' a telephone receiver of the type described, a bridge of metal foil, composed of a plurality of sections which are disposed between two adjacent parallel planes, substantially at right angles thereto, some of the sections being disposed face to face in substantially parallel relation and in close proximity to each other.

3. In a telephone receiver of the type described, a bridge of metal foil, composed of a relatively/*large number of sections which are disposed between two adjacent parallel planes substantially at right angle thereto, the sections being formed in groups the members of which are substantially parallel and in close proximity to each other.

4. In a telephone receiver of the type described, a bridge of met-al foil, composed of a plurality of Sections disposed between two adjacent parallel planes substantially at right angle thereto and in close proximity to one another, the sections being arranged in groups the members of which are parallel to one another.

5. In a telephone receiver of the type desupporting the bridge, some of the sections being disposed face to face and in substantially parallel relation to each other.

7. In a telephone receiver of the type described, a bridge of metal foil having a plurality of convolutions disposed in the same general plane and in close proximity to each other, a base of insulating material and pegs secured in the base for supporting 'the bridge in parallelism with the surface of the base.

In testimony whereof we have signed our names to this specification.

ALFRED WILLIAMS. LEO DAFT WILLIAMS. 

